Related papers: Identification of the ionizing source of NGC 2024
We re-examine the nature of NGC2024-IRS2 in light of the recent discovery of the late O-type star, IRS2b, located 5 arcsec from IRS2. Using L-band spectroscopy, we set a lower limit of Av = 27.0 mag on the visual extinction towards IRS2.…
We conducted wide-field JHKs imaging polarimetry toward NGC 2024. We found a prominent and extended polarized nebula over NGC 2024, and constrained the location of illuminating source of the nebula through the analysis of polarization…
We present a multi-wavelength observational study of the NGC 2024 filament using infrared to sub-millimeter continuum and the NH$_3$ $(1,1)$ and $(2,2)$ inversion transitions centered on FIR-3, the most massive core therein. FIR-3 is found…
We present results of a sensitive 76 ksec Chandra observation of the young stellar cluster in NGC 2024 (d = 415 pc) in the Orion B giant molecular cloud. Previous infrared observations have shown that this remarkable cluster contains…
We present first results of XMM-Newton X-ray observations of the infrared cluster lying near the NGC 2071 reflection nebula in the Orion B region. This cluster is of interest because it is one of the closest regions known to harbor embedded…
The NGC 2024 FIR 5/6 region was observed in the 6.9 mm continuum with an angular resolution of about 1.5 arcsec. The 6.9 mm continuum map shows four compact sources, FIR 5w, 5e, 6c, and 6n, as well as an extended structure of the ionization…
We present deep 3.6 cm radio continuum observations of the H II region NGC 2024 in Orion B obtained using the Very Large Array in its A-configuration, with $0\rlap.{''}2$ angular resolution. We detect a total of 25 compact radio sources in…
We have observed the ultracompact HII region G29.96-0.02 in the near infrared J, H, and K bands and in the Br-gamma line. By comparison with radio observations, we determine that the extinction to the nebula is AK = 2.14 with a 3 sigma…
NGC 6302 is one of the highest ionization planetary nebulae known and shows emission from species with ionization potential >300eV. The temperature of the central star must be >200,000K to photoionize the nebula, and has been suggested to…
The composite galaxy NGC 4102 hosts a LINER nucleus and a starburst. We mapped NGC 4102 in the 12.8 micron line of [NeII], using the echelon spectrometer TEXES on the NASA IRTF, to obtain a data cube with 1.5" spatial and 25 km/s spectral,…
We present observations of the starburst galaxy NGC 7714 with the Infrared Spectrograph IRS on board the Spitzer Space Telescope. The spectra yield a wealth of ionic and molecular features that allow a detailed characterization of its…
A deep 75 ks {\it Chandra} ACIS--I data of NGC 2024 was analyzed, aiming at a search for diffuse X-ray emission in this one of the most nearby (415 pc) massive star-forming regions. After removing point sources, an extended emission was…
We present results of a sensitive Chandra X-ray observation and Spitzer mid-IR observations of the infrared cluster lying north of the NGC 2071 reflection nebula in the Orion B molecular cloud. We focus on the dense cluster core known as…
Using the NIFS near-infrared integral-field spectrograph behind the facility adaptive optics module, ALTAIR, on Gemini North, we have identified several massive O-type stars that are responsible for the ionization of the Galactic…
Hidden from optical view in the starburst region of the dwarf galaxy NGC 5253 lies an intense radio source with an unusual spectrum which could be interpreted variously as nebular gas ionized by a young stellar cluster or nonthermal…
We report NIR broad and narrow band photometric observations in the direction of the IRAS17149-3916 source that reveal the presence of a young cluster of massive stars embedded in an HII region coincident with RCW121. These observations,…
We report on the discovery of several compact regions of mid-infrared emission in the starforming circum nuclear disk of the starburst/Seyfert2 galaxy NGC7582. The compact sources do not have counterparts in the optical and near-infrared,…
Aims: A near-infrared study of the main ionizing star of the ultracompact HII region G23.96+0.15 (IRAS 18317-0757) is presented, along with a re-evaluation of the distance to this source, and a re-assessment of H- and K-band classification…
We studied the multiband properties of two ultraluminous X-ray sources (2CXO J225728.9-410211 = X-1 and 2CXO J225724.7-410343 = X-2) and their surroundings, in the spiral galaxy NGC 7424. Both sources have approached X-ray luminosities…
We present a mid-infrared study of NGC 3576. The high-resolution images were taken at the Gemini South Observatory through narrow and broad band filters centered between 7.9 micron and 18 micron. The nearly diffraction limited images show…